A Player's Guide to Chords and Harmony (31 page)

Figure 7-29. The traditional spelling of the dominant-type chord in this progression (a) makes more sense in terms of the chromatic upward movement of the top voice. But the spelling in (b), which makes the chord easier to read, tends to be preferred by musicians today. Perhaps this is because the chord is just as likely to resolve downward, as shown in (c). A pre-20th-century classical composer would have been unlikely to use this resolution, because of the parallel 5ths.

THE WHOLE-TONE SCALE

There's no law that says scales always have to have exactly two half-steps. If we eliminate half-steps entirely, the result is the whole-tone scale (see Figure 7-30). This scale contains only whole-steps. The whole-tone scale is symmetrical with respect to the tonic. With the major and ascending melodic minor modes, when we choose a different tonic note to start and end on, the sound of the scale changes. But no matter which note of a whole-tone scale we start and end on, the scale sounds exactly the same.

Because the chromatic scale contains 12 tones while each whole-tone scale contains six, there are only two whole-tone scales. This fact is a boon to instrumentalists: They only have to learn two fingerings to be able to play whole-tone scales in all 12 keys.

The whole-tone scale is ideal for playing above 765 and 7#5 chords, as Figure 7-31 shows. All of the chord tones are found in the scale.

Figure 7-30. The two whole-tone scales. These scales have to be written using a diminished 3rd interval, but all of the steps are the same size.

Figure 7-31. A whole-tone scale works well for melodies above a dominant chord containing a #5 or 65 (or both).

THE DIMINISHED SCALE

Another symmetrical scale is known as the diminished scale (see Figure 7-32). It gets its name from the fact that it's constructed using all of the notes of two different diminished 7th chords. There are exactly three diminished scales in all, a fact you should verify for yourself by picking them out on the keyboard. As with diminished 7th chords, each scale has four notes that can be looked at interchangeably as the root.

We can look at a diminished scale as starting with either a half-step or a whole-step. The former turns out to be more useful when this scale is being used for soloing. Over the dominant 7th chord shown in Figure 7-33, voiced in a standard way with no 5th, all of the steps of the diminished scale can easily be heard as chord tones.

Figure 7-32. There are three diminished scales. Each contains the same pattern of alternating whole-steps and half-steps.

Figure 7-33. If we consider the diminished scale as starting with a half-step, all of the notes in the scale are chord tones above a dominant 7th chord with no 5th.

The diminished scale also contains major triads, but to get them, we have to skip a scale step. In the scale in Figure 7-33, for instance, the first, fourth, and sixth steps outline the C major triad implied by the left-hand chord. Figure 7-34 shows the major triads in this scale. If you're interested in bitonal music or progressions with ambiguous tonal centers, you might find this progression worth playing around with.

Figure 7-34. If we consider a diatonic triad as containing the root 3rd, and 5th steps of the scale (or the 2nd, 4th, and 6th steps, or whatever), all of the diatonic triads of a diminished scale are diminished. Even so, the scale contains four major triads. Shown here are the major triads found in the C diminished scale in Figure 7-33.

PENTATONIC SCALES

The major and ascending melodic minor modes are all seven-note scales. The whole-tone scale has only six notes, while the diminished scale has eight notes. Another useful group of scales contains only five notes per scale. These scales are known collectively as pentatonic scales. ("Penta-" is a Greek prefix that means "five") Since there are 12 notes in the chromatic scale, you might expect that we could construct quite a variety of scales by choosing five of the notes at a time. Only a few pentatonic scales are in common use, however.

The most important are the major and minor pentatonic scales, which are shown in Figure 7-35. These scales contain no half-steps, only whole-steps and minor thirds. In fact, they both have the same underlying pattern of whole-steps and minor thirds (W-W-M linked to W-M). As a result, it's easy to see that the C minor pentatonic contains the same notes as the E6 major pentatonic.

Figure 7-35. The major pentatonic and minor pentatonic scales (left and right, respectively). These scales contain minor 3rds, which are marked with a V. I've placed the upper tonic note in parentheses to remind you that the reason these scales are called pentatonic is because they contain five different tones. The sixth note is the octave.

Figure 7-36. The C major pentatonic can be used for soloing above any of the chords shown here. Okay, maybe the F#7#9 is a stretch, but a jazz soloist wouldn't have a problem with it. As an exercise, you should work out the harmonic function of each of the notes in the scale with reference to each chord root. Above the Dm7, for instance, the G in the scale is an added 4th.

Playing an F# major or D# minor pentatonic scale on the keyboard is easy: just play the black keys.

Pentatonic scales of this type are often used for soloing, because a single scale will work above more than one chord. A few possibilities are shown in Figure 7-36. As you can see from this figure, the C major pentatonic is compatible with both Cmaj7 and C7 chords.

Other pentatonic scales are used in musical traditions from Asia and Africa. Since these traditions don't use equal-tempered tuning, they can only be approximated by Western instruments, but they can give your music an exotic flavor that you may find worth cultivating. A couple of non-Western pentatonics are shown in Figure 7-37. When using these scales, it may be a good idea to avoid non-scale tones: As you add other notes, the pentatonics will start to sound like conventional Western modes.

Figure 7-37. These pentatonic scales are used more often in music of Asia and Africa than in Western music, but they're worth experimenting with. Try improvising a short piece using one of them without adding any non-scale tones.